This research program will investigate the molecular mechanisms which carry out the effects of cyclic AMP and cyclic CMP on the cornea. This includes the localization of beta-adrenergic and muscarinic cholinergic receptors within the corneal epithelium using radioligand binding to isolated subpopulation of basal, winged and superficial eptithelial cells and photoaffinity labeling techniques in situ. The observed cyclic AMP inhibition of collagen and glycosaminoglycan production by bovine keratocytes will be characterized and the mechanism identified. These studies will be extended to other corneal cells (bovine and human) in culture. A comparative biochemical examination of cyclic nucleotide-related enzymes will be made on corneal endothelia of species which have "regenerative" (rabbit and bovine) vs. "nonregenerative" (cat and human) endothelial cells. This knowledge will be used to develop drug regimens to pharmacologically stimulate endothelial proliferation in wounded cat and human corneas in organ culture. The prostaglandin synthetic pathways of corneal cells will be examined using a new, simple technique for separation and identification of prostaglandin-like substances.